Re: what are the best options for Workflows in SharePoint 2016

My two cents here:(1) SPO: Flow(2) SharePoint 2016 OnPremises: SP 2013 style workflows workflows so you have to author them using SPD 2013 or Visual Studio. As an alternative to native workflows, you might explore third party workflow produts

RE: what are the best options for Workflows in SharePoint 2016

You can use SharePoint 2010, 2013 (Workflow Manager), and Microsoft Flow
in both environments. SharePoint 2013 workflows on-prem requires
configuring Workflow Manager server. Workflow Manager itself has no
further investments by Microsoft. The modern workflow engine is
Microsoft Flow. You can use Flow with on-prem via the Microsoft Data
Gateway available from
https://docs.microsoft.com/en-us/power-bi/service-gateway-onprem. Only
Flows can be shared between on-prem and online without redeployment of
the workflow.